perf_counter tools: add in basic glue from Git

First very raw version at having a central 'perf' command and
a list of subcommands:

  perf top
  perf stat
  perf record
  perf report
  ...

This is done by picking up Git's collection of utility functions,
and hacking them to build fine in this new environment.

Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 463 insertions, 0 deletions

diff --git a/Documentation/perf_counter/builtin-help.c b/Documentation/perf_counter/builtin-help.c
new file mode 100644
index 000000000000..125fcc2f4901
--- /dev/null
+++ b/Documentation/perf_counter/builtin-help.c
@@ -0,0 +1,463 @@
+/*
+ * builtin-help.c
+ *
+ * Builtin help command
+ */
+#include "cache.h"
+#include "builtin.h"
+#include "exec_cmd.h"
+#include "common-cmds.h"
+#include "parse-options.h"
+#include "run-command.h"
+#include "help.h"
+
+static struct man_viewer_list {
+        struct man_viewer_list *next;
+        char name[FLEX_ARRAY];
+} *man_viewer_list;
+
+static struct man_viewer_info_list {
+        struct man_viewer_info_list *next;
+        const char *info;
+        char name[FLEX_ARRAY];
+} *man_viewer_info_list;
+
+enum help_format {
+        HELP_FORMAT_MAN,
+        HELP_FORMAT_INFO,
+        HELP_FORMAT_WEB,
+};
+
+static int show_all = 0;
+static enum help_format help_format = HELP_FORMAT_MAN;
+static struct option builtin_help_options[] = {
+        OPT_BOOLEAN('a', "all", &show_all, "print all available commands"),
+        OPT_SET_INT('m', "man", &help_format, "show man page", HELP_FORMAT_MAN),
+        OPT_SET_INT('w', "web", &help_format, "show manual in web browser",
+                        HELP_FORMAT_WEB),
+        OPT_SET_INT('i', "info", &help_format, "show info page",
+                        HELP_FORMAT_INFO),
+        OPT_END(),
+};
+
+static const char * const builtin_help_usage[] = {
+        "perf help [--all] [--man|--web|--info] [command]",
+        NULL
+};
+
+static enum help_format parse_help_format(const char *format)
+{
+        if (!strcmp(format, "man"))
+                return HELP_FORMAT_MAN;
+        if (!strcmp(format, "info"))
+                return HELP_FORMAT_INFO;
+        if (!strcmp(format, "web") || !strcmp(format, "html"))
+                return HELP_FORMAT_WEB;
+        die("unrecognized help format '%s'", format);
+}
+
+static const char *get_man_viewer_info(const char *name)
+{
+        struct man_viewer_info_list *viewer;
+
+        for (viewer = man_viewer_info_list; viewer; viewer = viewer->next)
+        {
+                if (!strcasecmp(name, viewer->name))
+                        return viewer->info;
+        }
+        return NULL;
+}
+
+static int check_emacsclient_version(void)
+{
+        struct strbuf buffer = STRBUF_INIT;
+        struct child_process ec_process;
+        const char *argv_ec[] = { "emacsclient", "--version", NULL };
+        int version;
+
+        /* emacsclient prints its version number on stderr */
+        memset(&ec_process, 0, sizeof(ec_process));
+        ec_process.argv = argv_ec;
+        ec_process.err = -1;
+        ec_process.stdout_to_stderr = 1;
+        if (start_command(&ec_process)) {
+                fprintf(stderr, "Failed to start emacsclient.\n");
+                return -1;
+        }
+        strbuf_read(&buffer, ec_process.err, 20);
+        close(ec_process.err);
+
+        /*
+         * Don't bother checking return value, because "emacsclient --version"
+         * seems to always exits with code 1.
+         */
+        finish_command(&ec_process);
+
+        if (prefixcmp(buffer.buf, "emacsclient")) {
+                fprintf(stderr, "Failed to parse emacsclient version.\n");
+                strbuf_release(&buffer);
+                return -1;
+        }
+
+        strbuf_remove(&buffer, 0, strlen("emacsclient"));
+        version = atoi(buffer.buf);
+
+        if (version < 22) {
+                fprintf(stderr,
+                        "emacsclient version '%d' too old (< 22).\n",
+                        version);
+                strbuf_release(&buffer);
+                return -1;
+        }
+
+        strbuf_release(&buffer);
+        return 0;
+}
+
+static void exec_woman_emacs(const char* path, const char *page)
+{
+        if (!check_emacsclient_version()) {
+                /* This works only with emacsclient version >= 22. */
+                struct strbuf man_page = STRBUF_INIT;
+
+                if (!path)
+                        path = "emacsclient";
+                strbuf_addf(&man_page, "(woman \"%s\")", page);
+                execlp(path, "emacsclient", "-e", man_page.buf, NULL);
+                warning("failed to exec '%s': %s", path, strerror(errno));
+        }
+}
+
+static void exec_man_konqueror(const char* path, const char *page)
+{
+        const char *display = getenv("DISPLAY");
+        if (display && *display) {
+                struct strbuf man_page = STRBUF_INIT;
+                const char *filename = "kfmclient";
+
+                /* It's simpler to launch konqueror using kfmclient. */
+                if (path) {
+                        const char *file = strrchr(path, '/');
+                        if (file && !strcmp(file + 1, "konqueror")) {
+                                char *new = strdup(path);
+                                char *dest = strrchr(new, '/');
+
+                                /* strlen("konqueror") == strlen("kfmclient") */
+                                strcpy(dest + 1, "kfmclient");
+                                path = new;
+                        }
+                        if (file)
+                                filename = file;
+                } else
+                        path = "kfmclient";
+                strbuf_addf(&man_page, "man:%s(1)", page);
+                execlp(path, filename, "newTab", man_page.buf, NULL);
+                warning("failed to exec '%s': %s", path, strerror(errno));
+        }
+}
+
+static void exec_man_man(const char* path, const char *page)
+{
+        if (!path)
+                path = "man";
+        execlp(path, "man", page, NULL);
+        warning("failed to exec '%s': %s", path, strerror(errno));
+}
+
+static void exec_man_cmd(const char *cmd, const char *page)
+{
+        struct strbuf shell_cmd = STRBUF_INIT;
+        strbuf_addf(&shell_cmd, "%s %s", cmd, page);
+        execl("/bin/sh", "sh", "-c", shell_cmd.buf, NULL);
+        warning("failed to exec '%s': %s", cmd, strerror(errno));
+}
+
+static void add_man_viewer(const char *name)
+{
+        struct man_viewer_list **p = &man_viewer_list;
+        size_t len = strlen(name);
+
+        while (*p)
+                p = &((*p)->next);
+        *p = calloc(1, (sizeof(**p) + len + 1));
+        strncpy((*p)->name, name, len);
+}
+
+static int supported_man_viewer(const char *name, size_t len)
+{
+        return (!strncasecmp("man", name, len) ||
+                !strncasecmp("woman", name, len) ||
+                !strncasecmp("konqueror", name, len));
+}
+
+static void do_add_man_viewer_info(const char *name,
+                                   size_t len,
+                                   const char *value)
+{
+        struct man_viewer_info_list *new = calloc(1, sizeof(*new) + len + 1);
+
+        strncpy(new->name, name, len);
+        new->info = strdup(value);
+        new->next = man_viewer_info_list;
+        man_viewer_info_list = new;
+}
+
+static int add_man_viewer_path(const char *name,
+                               size_t len,
+                               const char *value)
+{
+        if (supported_man_viewer(name, len))
+                do_add_man_viewer_info(name, len, value);
+        else
+                warning("'%s': path for unsupported man viewer.\n"
+                        "Please consider using 'man.<tool>.cmd' instead.",
+                        name);
+
+        return 0;
+}
+
+static int add_man_viewer_cmd(const char *name,
+                              size_t len,
+                              const char *value)
+{
+        if (supported_man_viewer(name, len))
+                warning("'%s': cmd for supported man viewer.\n"
+                        "Please consider using 'man.<tool>.path' instead.",
+                        name);
+        else
+                do_add_man_viewer_info(name, len, value);
+
+        return 0;
+}
+
+static int add_man_viewer_info(const char *var, const char *value)
+{
+        const char *name = var + 4;
+        const char *subkey = strrchr(name, '.');
+
+        if (!subkey)
+                return error("Config with no key for man viewer: %s", name);
+
+        if (!strcmp(subkey, ".path")) {
+                if (!value)
+                        return config_error_nonbool(var);
+                return add_man_viewer_path(name, subkey - name, value);
+        }
+        if (!strcmp(subkey, ".cmd")) {
+                if (!value)
+                        return config_error_nonbool(var);
+                return add_man_viewer_cmd(name, subkey - name, value);
+        }
+
+        warning("'%s': unsupported man viewer sub key.", subkey);
+        return 0;
+}
+
+static int perf_help_config(const char *var, const char *value, void *cb)
+{
+        if (!strcmp(var, "help.format")) {
+                if (!value)
+                        return config_error_nonbool(var);
+                help_format = parse_help_format(value);
+                return 0;
+        }
+        if (!strcmp(var, "man.viewer")) {
+                if (!value)
+                        return config_error_nonbool(var);
+                add_man_viewer(value);
+                return 0;
+        }
+        if (!prefixcmp(var, "man."))
+                return add_man_viewer_info(var, value);
+
+        return perf_default_config(var, value, cb);
+}
+
+static struct cmdnames main_cmds, other_cmds;
+
+void list_common_cmds_help(void)
+{
+        int i, longest = 0;
+
+        for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
+                if (longest < strlen(common_cmds[i].name))
+                        longest = strlen(common_cmds[i].name);
+        }
+
+        puts("The most commonly used perf commands are:");
+        for (i = 0; i < ARRAY_SIZE(common_cmds); i++) {
+                printf("   %s   ", common_cmds[i].name);
+                mput_char(' ', longest - strlen(common_cmds[i].name));
+                puts(common_cmds[i].help);
+        }
+}
+
+static int is_perf_command(const char *s)
+{
+        return is_in_cmdlist(&main_cmds, s) ||
+                is_in_cmdlist(&other_cmds, s);
+}
+
+static const char *prepend(const char *prefix, const char *cmd)
+{
+        size_t pre_len = strlen(prefix);
+        size_t cmd_len = strlen(cmd);
+        char *p = malloc(pre_len + cmd_len + 1);
+        memcpy(p, prefix, pre_len);
+        strcpy(p + pre_len, cmd);
+        return p;
+}
+
+static const char *cmd_to_page(const char *perf_cmd)
+{
+        if (!perf_cmd)
+                return "perf";
+        else if (!prefixcmp(perf_cmd, "perf"))
+                return perf_cmd;
+        else if (is_perf_command(perf_cmd))
+                return prepend("perf-", perf_cmd);
+        else
+                return prepend("perf", perf_cmd);
+}
+
+static void setup_man_path(void)
+{
+        struct strbuf new_path = STRBUF_INIT;
+        const char *old_path = getenv("MANPATH");
+
+        /* We should always put ':' after our path. If there is no
+         * old_path, the ':' at the end will let 'man' to try
+         * system-wide paths after ours to find the manual page. If
+         * there is old_path, we need ':' as delimiter. */
+        strbuf_addstr(&new_path, system_path(PERF_MAN_PATH));
+        strbuf_addch(&new_path, ':');
+        if (old_path)
+                strbuf_addstr(&new_path, old_path);
+
+        setenv("MANPATH", new_path.buf, 1);
+
+        strbuf_release(&new_path);
+}
+
+static void exec_viewer(const char *name, const char *page)
+{
+        const char *info = get_man_viewer_info(name);
+
+        if (!strcasecmp(name, "man"))
+                exec_man_man(info, page);
+        else if (!strcasecmp(name, "woman"))
+                exec_woman_emacs(info, page);
+        else if (!strcasecmp(name, "konqueror"))
+                exec_man_konqueror(info, page);
+        else if (info)
+                exec_man_cmd(info, page);
+        else
+                warning("'%s': unknown man viewer.", name);
+}
+
+static void show_man_page(const char *perf_cmd)
+{
+        struct man_viewer_list *viewer;
+        const char *page = cmd_to_page(perf_cmd);
+        const char *fallback = getenv("PERF_MAN_VIEWER");
+
+        setup_man_path();
+        for (viewer = man_viewer_list; viewer; viewer = viewer->next)
+        {
+                exec_viewer(viewer->name, page); /* will return when unable */
+        }
+        if (fallback)
+                exec_viewer(fallback, page);
+        exec_viewer("man", page);
+        die("no man viewer handled the request");
+}
+
+static void show_info_page(const char *perf_cmd)
+{
+        const char *page = cmd_to_page(perf_cmd);
+        setenv("INFOPATH", system_path(PERF_INFO_PATH), 1);
+        execlp("info", "info", "perfman", page, NULL);
+}
+
+static void get_html_page_path(struct strbuf *page_path, const char *page)
+{
+        struct stat st;
+        const char *html_path = system_path(PERF_HTML_PATH);
+
+        /* Check that we have a perf documentation directory. */
+        if (stat(mkpath("%s/perf.html", html_path), &st)
+            || !S_ISREG(st.st_mode))
+                die("'%s': not a documentation directory.", html_path);
+
+        strbuf_init(page_path, 0);
+        strbuf_addf(page_path, "%s/%s.html", html_path, page);
+}
+
+/*
+ * If open_html is not defined in a platform-specific way (see for
+ * example compat/mingw.h), we use the script web--browse to display
+ * HTML.
+ */
+#ifndef open_html
+void open_html(const char *path)
+{
+        execl_perf_cmd("web--browse", "-c", "help.browser", path, NULL);
+}
+#endif
+
+static void show_html_page(const char *perf_cmd)
+{
+        const char *page = cmd_to_page(perf_cmd);
+        struct strbuf page_path; /* it leaks but we exec bellow */
+
+        get_html_page_path(&page_path, page);
+
+        open_html(page_path.buf);
+}
+
+int cmd_help(int argc, const char **argv, const char *prefix)
+{
+        int nonperf;
+        const char *alias;
+        load_command_list("perf-", &main_cmds, &other_cmds);
+
+        /* setup_perf_directory_gently(&nonperf); */
+        perf_config(perf_help_config, NULL);
+
+        argc = parse_options(argc, argv, builtin_help_options,
+                        builtin_help_usage, 0);
+
+        if (show_all) {
+                printf("usage: %s\n\n", perf_usage_string);
+                list_commands("perf commands", &main_cmds, &other_cmds);
+                printf("%s\n", perf_more_info_string);
+                return 0;
+        }
+
+        if (!argv[0]) {
+                printf("usage: %s\n\n", perf_usage_string);
+                list_common_cmds_help();
+                printf("\n%s\n", perf_more_info_string);
+                return 0;
+        }
+
+        alias = alias_lookup(argv[0]);
+        if (alias && !is_perf_command(argv[0])) {
+                printf("`perf %s' is aliased to `%s'\n", argv[0], alias);
+                return 0;
+        }
+
+        switch (help_format) {
+        case HELP_FORMAT_MAN:
+                show_man_page(argv[0]);
+                break;
+        case HELP_FORMAT_INFO:
+                show_info_page(argv[0]);
+                break;
+        case HELP_FORMAT_WEB:
+                show_html_page(argv[0]);
+                break;
+        }
+
+        return 0;
+}